At 1-3, the Arizona Cardinals need a Week 5 win to turn their season around. A Thursday Night Football showdown against the fellow NFC West bottom feeder San Francisco 49ers may be just what the Cardinals need.

Arizona opened the preseason with the fifth-best odds to win Super Bowl LI, but has stumbled out of the gate. An opening night loss to New England at home was followed by a 40-7 rout over Tampa Bay, but the Cardinals are 0-2 since then. Even worse, those losses have come against teams who were expected to watch the playoffs from home this season, Buffalo and Los Angeles.

A rebound may have to happen without quarterback Carson Palmer. He left last week’s loss to the Rams with a head injury in the fourth quarter and has since been in the league’s concussion protocol. He has yet to be cleared and will sit out Thursday night.

Losing their veteran leader may not be entirely fatal for the Cardinals. Palmer led this team to an NFC Championship appearance last season, but had been ineffective this fall. The veteran saw his QB rating drop from 104.6 in 2015 to 81.9 this season while posting just a 6-to-5 touchdown-to-interception ratio. On Thursday, he’ll be replaced by Drew Stanton, who was suboptimal in relief last week. The veteran backup completed just 4 of 11 passes and threw a pair of interceptions as Arizona choked away a winnable home game.

San Francisco, despite standing at 1-3, has arguably been better than expected after two years of personnel losses and extremely low expectations. The 49ers kicked off their season with a 28-0 stomping of the now 3-1 Rams, but haven’t been nearly as successful since thanks to a brutal schedule that included road contests at Carolina and Seattle. Back-to-back 19-point losses followed before a competitive 24-17 defeat at the hands of Dallas.

That Cowboys loss featured a moderately decent performance from Blaine Gabbert, who might just be the worst starting quarterback in the country. The veteran passer completed 16 of his 23 passes, but still found the end zone only once in a game the Niners lost by a single touchdown. He’ll have to be better on Thursday to lead San Francisco to win No. 2, but it won’t be easy against a Cardinals defense only allowing 20 points per game this season. Arizona is currently ranked eighth in the NFL in terms of yards allowed in 2016.

That’s a strong return from a team that added Chandler Jones this offseason to bolster its pass rush, but this stingy defense has yet to translate into wins. The Cardinals have been moving the ball relatively well — they rank seventh in the league in yards per game — but have struggled to turn yardage and field position into points. Only 57 percent of the team’s trips to the red zone have resulted in touchdowns.

That figure stands to remain flat if Palmer can’t play on Thursday. Stanton hasn’t thrown a touchdown pass since December 2014.